11. The engine has a four-valve head with splayed rocker arms to actuate the valves. 12. Low-friction, roller-bearing rocker arms are used to help reduce friction and improve engine efficiency. 13. Titanium is used for the valves and the rocker arms have a diamond-like coating. 14. Some overhead camshaft designs still have rocker arms ; this facilitates adjustment of mechanical clearances. 15. Thus, the rocker arm geometry is stated to be over-arcing. 16. The rocker arms are constructed using metal injection molding. 17. Hydraulic lash adjusters mounted on the rocker arms are used to provide zero valve lash. 18. Needle bearings are heavily used in automobile components such as rocker arm pivots, pumps, slopes. 19. Every cylinder head has four overhead valves, which are activated by tappets, pushrods and rocker arms . 20. The pistons are resin-coated and lightweight aluminum material is used for the friction-reducing roller rocker arm .
